🔗 Share this article

Light therapy is clearly enjoying a wave of attention. Consumers can purchase glowing gadgets for everything from dermatological concerns and fine lines to aching tissues and oral inflammation, recently introduced is a toothbrush outfitted with tiny red LEDs, described by its makers as “a significant discovery for domestic dental hygiene.” Worldwide, the industry reached $1 billion in 2024 and is forecast to expand to $1.8 billion by 2035. There are even infrared saunas available, where instead of hot coals (real or electric) heating the air, the infrared radiation heats your body itself. According to its devotees, it feels similar to a full-body light therapy session, enhancing collagen production, easing muscle tension, relieving inflammation and long-term ailments as well as supporting brain health.

Understanding the Evidence

“It sounds a bit like witchcraft,” notes Paul Chazot, a scientist who has studied phototherapy extensively. Certainly, we know light influences biological functions. Our bodies produce vitamin D through sun exposure, crucial for strong bones, immune defense, and tissue repair. Natural light synchronizes our biological clocks, as well, activating brain chemicals and hormonal responses in daylight, and signaling the body to slow down for nighttime. Daylight-simulating devices are a common remedy for people with seasonal affective disorder (Sad) to boost low mood in winter. Clearly, light energy is essential for optimal functioning.

Types of Light Therapy

While Sad lamps tend to use a mixture of light frequencies from the blue end of the spectrum, the majority of phototherapy tools use red or near-infrared wavelengths. In rigorous scientific studies, such as Chazot’s investigations into the effects of infrared on brain cells, determining the precise frequency is essential. Light constitutes electromagnetic energy, which runs the spectrum from the lowest-energy, longest wavelengths (radio waves) to high-energy gamma radiation. Therapeutic light application employs mid-spectrum wavelengths, with ultraviolet representing the higher energy invisible light, then the visible spectrum we perceive as colors and then infrared (which we can see with night-vision goggles).

Ultraviolet treatment has been employed by skin specialists for decades for addressing long-term dermatological issues like vitiligo. It affects cellular immune responses, “and suppresses swelling,” notes Dr Bernard Ho. “Considerable data validates phototherapy.” UVA goes deeper into the skin than UVB, whereas the LEDs we see on consumer light-therapy devices (usually producing colored light emissions) “generally affect surface layers.”

Risk Assessment and Professional Supervision

The side-effects of UVB exposure, like erythema or pigmentation, are well known but in medical devices the light is delivered in a “narrow-band” form – signifying focused frequency bands – that reduces potential hazards. “It’s supervised by a healthcare professional, meaning intensity is regulated,” says Ho. And crucially, the lightbulbs are calibrated by medical technicians, “to confirm suitable light frequency output – as opposed to commercial tanning facilities, where oversight might be limited, and emission spectra aren’t confirmed.”

Commercial Products and Research Limitations

Colored light diodes, he notes, “aren’t really used in the medical sense, but could assist with specific concerns.” Red wavelength therapy, proponents claim, help boost blood circulation, oxygen uptake and cell renewal in the skin, and promote collagen synthesis – a primary objective in youth preservation. “The evidence is there,” says Ho. “However, it’s limited.” Nevertheless, given the plethora of available tools, “we don’t know whether or not the lights emitted are reflective of the research that has been done. Appropriate exposure periods aren’t established, how close the lights should be to the skin, if benefits outweigh potential risks. There are lots of questions.”

Targeted Uses and Expert Opinions

Initial blue-light devices addressed acne bacteria, microorganisms connected to breakouts. Scientific backing remains inadequate for regular prescription – although, notes the dermatologist, “it’s frequently employed in beauty centers.” Some of his patients use it as part of their routine, he says, though when purchasing home devices, “we recommend careful testing and security confirmation. If it’s not medically certified, oversight remains ambiguous.”

Advanced Research and Cellular Mechanisms

Simultaneously, in advanced research areas, Chazot has been experimenting with brain cells, revealing various pathways for light-enhanced cell function. “Pretty much everything I did with the light at that particular wavelength was positive and protective,” he says. Multiple claimed advantages have created skepticism toward light treatment – that it’s too good to be true. But his research has thoroughly changed his mind in that respect.

The researcher primarily focuses on pharmaceutical solutions for brain disorders, though twenty years earlier, a doctor developing photonic antiviral treatment consulted his scientific background. “He created some devices so that we could work with them with cells and with fruit flies,” he explains. “I remained doubtful. The specific wavelength measured approximately 1070nm, that many assumed was biologically inert.”

Its beneficial characteristic, nevertheless, was its efficient water penetration, allowing substantial bodily penetration.

Mitochondrial Effects and Brain Health

Additional research indicated infrared affected cellular mitochondria. Mitochondria are the powerhouses of cells, producing fuel for biological processes. “Mitochondria exist throughout the body, including the brain,” notes the researcher, who, as a neuroscientist, decided to focus the research on brain cells. “Research confirms improved brain blood flow with phototherapy, which is consistently beneficial.”

With 1070 treatment, cellular power plants create limited oxidative molecules. In limited quantities these molecules, says Chazot, “stimulates so-called chaperone proteins which look after your mitochondria, look after your cells and also deal with the unwanted proteins.”

These processes show potential for neurological conditions: free radical neutralization, inflammation reduction, and waste removal – autophagy representing cellular waste disposal.

Ongoing Study Progress and Specialist Evaluations

The last time Chazot checked the literature on using the 1070 wavelength on human dementia patients, he reports, about 400 people were taking part in four studies, including his own initial clinical trials in the US